package main

import (
	"context"
	"fmt"
	"github.com/olivere/elastic/v7"
	"log"
	"os"
	"reflect"
)

type Employee struct {
	FirstName string   `json:"first_name"`
	LastName  string   `json:"last_name"`
	Age       int      `json:"age"`
	About     string   `json:"about"`
	Interests []string `json:"interests"`
}

var client *elastic.Client
var host = "http://127.0.0.1:9200/"

func init() {
	errorlog := log.New(os.Stdout,"APP",log.LstdFlags)
	var err error
	client,err =elastic.NewClient(elastic.SetErrorLog(errorlog),elastic.SetURL(host))
	if err !=nil {
		log.Panic(err)
	}
	info, code, err := client.Ping(host).Do(context.TODO())
	if err != nil {
		log.Panic(err)
	}
	fmt.Printf("Elasticsearch returned with code %d and version %s\n", code, info.Version.Number)
   esversion,err :=  client.ElasticsearchVersion(host)
	if err != nil {
		log.Panic(err)
	}
	fmt.Printf("Elasticsearch version %s\n", esversion)
}
func create(){
	//使用结构体
	e1 := Employee{"Jane", "Smith", 32, "I like to collect rock albums", []string{"music"}}
	put1, err :=client.Index().
		Index("megacorp").
		Type("employee").
		Id("1").
		BodyJson(e1).
		Do(context.TODO())
	if err != nil {
		panic(err)
	}
	fmt.Printf("Indexed tweet %s to index s%s, type %s\n", put1.Id, put1.Index, put1.Type)
	//使用字符串
	e2 := `{"first_name":"John","last_name":"Smith","age":25,"about":"I love to go rock climbing","interests":["sports","music"]}`
    put2,err := client.Index().
    	Index("megacorp").
    	Type("employee").
    	Id("2").
    	BodyJson(e2).
    	Do(context.TODO())
	if err != nil {
		panic(err)
	}
	fmt.Printf("Indexed tweet %s to index s%s, type %s\n", put2.Id, put2.Index, put2.Type)
}
//删除
func  delete()  {
	res, err := client.Delete().Index("megacorp").Id("1").Do(context.TODO())
	if err != nil {
		println(err.Error())
		return
	}
	fmt.Printf("delete result %s\n", res.Result)

}
//修改
func  update()  {
	res, err := client.Update().Index("megacorp").
		Type("employee").
		Id("2").
		Doc(map[string]interface{}{"age":88}).
		Do(context.TODO())
	if err != nil {
		println(err.Error())
	}
	fmt.Printf("update age %s\n", res.Result)
}
//查找
func gets(){
	get1, err := client.Get().Index("megacorp").Type("employee").Id("2").Do(context.Background())
	if err != nil {
		panic(err)
	}
	if get1.Found{
		fmt.Printf("Got document %s in version %d from index %s, type %s\n", get1.Id, get1.Version, get1.Index, get1.Type)
	}
}
//搜索
func query() {
	var res *elastic.SearchResult
	var err error
	//取所有
	res, err = client.Search("megacorp").Type("employee").Do(context.Background())
	printEmployee(res,err)
	//字段相同
	q :=elastic.NewQueryStringQuery("last_name:Smith")
	res, err = client.Search("megacorp").Type("employee").Query(q).Do(context.Background())
	if err != nil {
		println(err.Error())
	}
	printEmployee(res, err)
	//条件查询
	//年龄大于30岁的
	boolQ := elastic.NewBoolQuery()
	boolQ.Must(elastic.NewMatchQuery("last_name", "smith"))
	boolQ.Filter(elastic.NewRangeQuery("age").Gt(30))
	res, err = client.Search("megacorp").Type("employee").Query(q).Do(context.Background())
	printEmployee(res, err)
	//短语搜索 搜索about字段中有 rock climbing
	matchPhraseQuery := elastic.NewMatchPhraseQuery("about","rock climbing")
	res, err = client.Search("megacorp").Type("employee").Query(matchPhraseQuery).Do(context.Background())
	printEmployee(res, err)
	//分析 interests
	aggs := elastic.NewTermsAggregation().Field("interests")
	res, err = client.Search("megacorp").Type("employee").Aggregation("all_interests", aggs).Do(context.Background())
	printEmployee(res, err)

}
//分页

func  list(size,page int)  {
	if size <0 || page <1 {
		fmt.Printf("param error")
		return
	}
	res, err :=client.Search("megacorp").Type("employee").Size(size).From(page -1 *size).Do(context.TODO())
	printEmployee(res, err)
}


////打印查询到的Employee
func  printEmployee(res *elastic.SearchResult,err error)  {
	if err != nil {
		print(err.Error())
		return
	}
	var typ Employee
	for _, item := range res.Each(reflect.TypeOf(typ)) {
		t := item.(Employee)
		fmt.Printf("%#v\n", t)
	}

}